Table 1.

The proposed typology for capturing COPD phenotypes

Type	Description	Example(s)
1) Problem	an overall category for any COPD indications of concern	frequent exacerbator
a) MedicalCondition*	any disease or medical condition; includes COPD comorbidities	emphysema, pulmonary vascular disease, asthma, congestive heart failure
b) RiskFactor*	a phenotype signifying a patient’s increased chances of having COPD	increased levels of the c-reactive protein, alpha1 antitrypsin deficiency
i) SignOrSymptom*	an observable irregularity manifested by a COPD patient	chronic cough, shortness of breath, purulent sputum production
ii) IndividualBehaviour*	a patient’s habits leading to susceptibility of having COPD	smoking for 25 years
iii) TestOrMeasureResult*	findings based on COPD-relevant examinations	increased white blood cell counts, FEV1 45% predicted
2) Treatment	any medication, therapy or program for treating COPD	oxygen therapy, pulmonary rehabilitation, pursed lips breathing
3) TestOrMeasure	an overall category for any COPD-relevant examinations or measures/parameters	increased compliance of the lung, FEV1, FEV1/FVC ratio
a) RadiologicalTest	any of the radiological tests for detecting COPD	computed tomography scanning, high resolution computed tomography
b) MicrobiologicalTest	an examination of a COPD- relevant specimen	complete blood count
c) PhysiologicalTest	a measurement of a COPD patient’s capacity to exercise	6-min walking distance

Types marked with an asterisk (*) were adapted from the PhenoCHF scheme.